CONTROL MATERIAL FOR THERMAL NEUTRON REACTOR CONTROL ROD AND THERMAL NEUTRON REACTOR CONTROL ROD

PROBLEM TO BE SOLVED : To provide a control material capable of coexisting with a fuel material during meltdown without being melted or partially evaporated before fuel damage even while obtaining reactivity at the same level as when a conventional control material is used and without being deposited and separated even when molten fuel re-solidifies. SOLUTION : The control material for thermal neutron reactor control rods consists of the sintered body of a mixture including a rare earth element oxide component A and a 4 group element oxide component B. The rare earth element oxide A is a europium oxide or a combination of one or more kinds selected from a group consisting of a samarium oxide, a gadolinium oxide and a dysprosium oxide and the europium oxide. The 4 group element oxide component B is one or more kinds selected from a group consisting of a zirconium oxide and a hafnium oxide. SELECTED DRAWING : Figure 1 COPYRIGHT : (C)2018, JPO&INPIT